Reliability and validity of measurements of cervical retraction strength obtained with a hand-held dynamometer

ABSTRACT

Objectives: The purpose of this study was to describe the reliability and validity of measurements of cervical retraction strength obtained with a hand held dynamometer (HHD) from healthy adults.

Background: Impaired neck muscle strength is related to neck pain, abnormal posture, and various cervical pathologies. While sophisticated devices to objectively measure neck strength exist, many are not practicable in typical orthopedic practices or have questionable validity and reliability.

Methods: Forty participants were included in the analysis of neck strength using isometric testing with an HHD fixed in a cradle on a table top. The highest neck retraction force recorded in Newtons (N) for each participant, was used for data analysis.

Results: Both intratester and intertester reliability were excellent as judged by intraclass correlation coefficients (ICCs) (.885 – .974) and minimal detectable change (MDC) (21.1 to 47.6 N). Validity was confirmed on the basis of expected gender and age differences (ie, men were stronger than women and younger participants were stronger than older participants).

Conclusion: Fixed HHD is a reliable and valid tool for measuring isometric neck retraction strength in ostensibly healthy adults. Its value in the assessment of individuals with neck pathology awaits further examination.

KEYWORDS:

• Cervical retraction
• hand held dynamometry
• isometric neck strength

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work received no external funding.

Notes on contributors

Frank Tudini

Dr. Frank Tudini is an Assistant Professor for the Department of Physical Therapy at Campbell University(CU), College of Pharmacy and Health Sciences (CPHS). He teaches musculoskeletal and clinical reasoning content. Dr. Tudini has been a Physical Therapist for over 15 years and was named a Board Certified Clinical Specialist in Orthopaedic Physical Therapy in 2012 by the American Physical Therapy Association and a Fellow in the American Academy of Orthopaedic Manual Physical Therapists in 2014. Research interests include manual therapy, particularly in the spine, and clinical reasoning.

Bradley Myers

Dr. Bradley Myers is an Assistant Professor within the Campbell University Doctor of Physical Therapy Program in Buies Creek, NC. He is recognized as a Board Certified Orthopaedic Specialist, Fellow of the American Academy of Orthopaedic Manual Physical Therapists, and has completed a Doctor of Science Degree in Orthopaedic Manual Physical Therapy. His research interests include the appropriate application of manual therapy techniques with exercise interventions within orthopaedic dysfunctions, and the identification of motor control dysfunctions as a precursor/result of musculoskeletal impairments.

Richard Bohannon

Dr. Richard Bohannon is Professor of Physical Therapy at Campbell University in Lillington, NC. Prior to joining the faculty at Campbell University Dr. Bohannon held numerous academic, researc, and clinical positions- most recently at the University of Connecticut. His clinical background includes work in acute care, rehabilitation, outpatient, and homecare settings. According to Google Scholar he is the author of over 400 peer-reviewed publications with over 28,000 citations. He has served as Editor in Chief of two Journals, on the Editorial Board of 15 other journals, and a reviewer for over 200 different journals.